Cooling apparatus



Dec. 30, 1941- J. NARSTED EI'AL COOLING APPARATUS 4 Shee'ts-Sheet 1Filed March 1, 1939 INVTORS ATTORNEYS Dec. 30, 1941. J. NARSTED ETALCOOLING APPARATUS Filed March 1, 1959 4 Sheets-Sheet 2 lNVENTORj R O ADec. 30, 1941.

J. NARSTED ETAL 2,268,296

COOLING APPARATUS Filed March 1, 1959 4 Sheets-Sheet 3 E J0 E 47 Z4 33J/ m *2 6 ll 1 5 E J0 6? J 1 5 4 g 68 73 as? W VII '1 kmmmlmm 3 73 /E M554 ATTORNEYS Dec. 30, 1941. J. NARSTED ET AL 2,268,296

COOLING APPARATUS Filed March 1, 1939 4 Sheets-Sheet 4 ATTO R N EY5Patentecl Dec. 3t), 1941 coosnzo Arrsm'rps llohn Narstcd, Montreal,

Povl ll. Lind, h F. L. Smidth n has, his

tion oi-New .llersey Application 1 ll (line.

This invention relates to apparatus for cooling, or otherwise treating,material in rotary drums by gaseous fluids.

MM ill N, w Yorh, N. W a

uchcc, @anada, and ignore to lit-l coral rich ll, i939, he! No. 259,292

(til.- di -W5) to compartments at the interior suri'ace oi the shell andthence through the material, the easeous fluid being introducedprincipally through those shell openings which at the time lie under thematerial in the drum.

In accordance with one phase oi our inven tion the wind-hon is supportedsolely by the rotary shell oi the drum preferably by means oi wheelsassociated with the wind-hon which operate on a track carried hy theshell, the wind hos being held relatively stationary as the shellrotates within it. no tar as this leature oi the invention is concernedthe wind-hon preferably completely encircles the shell oi the drum, hutso far as other features oi the invention are con cerned it isimmaterial whether it extends entirely around'the shell oi the drum ornot:

The discharge outlet oi the wind-hon faces the drum shell, and theopenings through the shell move directly under the wind hou and over itsdischarge outlet. The shell op 1: v positioned that when the aircompartments within the shell are arranged in two circumien ential rows,each shell opening lies partly to one side of the partition whichseparates the rows of air compartments and partly to the other sidethereof, so that the air admitted through the shell openings will bedivided and part will pass to the air compartments at one side oi thepartition while the rest will pass to the air vcompartments at itsopposite side. Preferably, a hood is placed within the shell over eachshell opening to prevent solid material from passing outwardly into thewind-box, and an adjustable plate is associated with the hood to change,when desired, the proportion of air admitted to the two rows of aircompartments.

A barrier is positioned in the wind-box at either side of the placewhere air is admitted to it. Each barrier completely spans the passagethrough the wind-box and is adjustable circumferentially of it to adjustnot only the circumferential length of the discharge outlet of thewind-box, but also thecircumferential length of the portion of thewind-box to which the air is admitted. Air is thus caused to flowprincipally through those shell openings which at the time lit lit

are opposite that portion of the wind-hon which lies between the twobarriers, the arrangement he such that these particular shell openingsare the ones which lie under the material with in the dr. Each barrieris provided with a rehle opeg to permit a small amount of air to passlay it into the portion of thevwindhon heyond the harrier to cool thecover plates oi the air compartments which lie above the level oi thematerial in the drum.

The cover plates for the air compartments are curved or inclined so thatthe trailing edge oi one. cover plate will overlap the leading edge oithe succeed one to provide suitable slot-like ones through which airpasses from the air compartments into the material within the d mo: Eachoi the cover plates is secured at its center portion only to the shelloi the drum.

The invention includes certain other improvements hereinafter described.

@ur improved apparatus was designed especially ior use in cooling cementclinker by means of air, hut it may be used for other purposes, and witha gaseous fluid other than air, and even tor heating or chemicallytreating material rather than cooling it. "However, for convenience theapparatus will hereinafter be designated a cooler and the gaseous fluidwill he referred to only as air.

in the accompanying drawings the improvemenis are illustrated inconnection with the cooling section oi a rotary tubular kiln, but itwill he understood that the improvements are applicable to a cooler thatis separate and distinct i'rom the kiln.

in the drawings:

his 1 is a transverse vertical section through the improved cooler thesection being taken on the line Il--i of Fig. 3;

Fig. 2 is a side elevation of the portion of the cooler shown in Fig. i:

Fig. 3 is a vertical longitudinal section through the cooler taken onthe line tt of Fig. i;

Fig. i is a transverse section taken on the line t-t of Fig. 3illustrating the manner in which the cover plates for the aircompartments are mounted;

Fig. 5 is a longitudinal section through one of the barrier blocksemployed in the wind-box;

Fig. 6 is an end view of the barrier block shown 'inFig.5;

Fig. 7 is an enlarged view of the upper portion of Fig. 3 with more ofthe parts shown in cross section;

Fig. 8 is a transverse section through the windbox .taken on the line6-6 of Fig. l with the barrier blocks omitted;

Fig. 9 is a section taken on the line 39 of Fig. 7 illustrating themeans for adjusting the wheeled shafts that carry the wind-box;

Fig. 10 is an end view of half of the cage that fits into the drum shelland forms the walls of the air compartments, this view. also. showingseveral sections of the sectional discharge ring;

Fig. 1l is a plan view of a portion of the cage as viewed outwardly fromits central axis;

Fig. 12 is a longitudinal section through the cage taken on the linel2-l2 of Fig. 11;

Fig. 13 is a longitudinal section through the cage taken on the lineI3l3 of Fig. 11;

Fig. 14 is a side elevation of a portion of one of the sectionalair-seal rings for the wind-box;

Fig. 15 is a transverse section taken on the line l5 l5 of Fig. 14; and

Fig. 16 is a detail view illustrating the manner in which an air seal iseffected at the adjoining ends of two sections of the air-seal ringshown in Fig. 14.

As above stated the improved cooler may be an independent one but in thedrawings it is illustrated in connection with a rotary kiln of the drumtype. The shell of the kiln is shown at i (Fig. 3) and has the usuallining 2. The shell is mounted to rotate about an axis which is slightlyinclined to the horizontal so that the material in the kiln, such ascement clinker, feeds towards its lower discharge end as the kilnrotates. In the present instance the shell 3 of the cooler forms acontinuation of the shell I of the kiln.

The shell of the cooler is provided with an external reinforcing band 4(Figs. 3 and 7) 'preferably welded in place. A pair of flanges 6 arewelded edgewise to the reinforcing band and to each of these flanges issecured one rail 6 of a track. Two pairs of wheels I (Figs. 1, 3and 7)are mounted to operate on the track formed by the rails 6. Each pair ofwheels is mounted on a shaft 8. The two shafts 8 support an annularwind-box preferably formed by fastening together two side plates 9 andI0 (Fig. 7) and an outerplate i I. The wind-box is thus channeledshapedin cross section with the opening I 2 of the channel facing the shell 3of the cooler. At spaced intervals within the wind-box are stiifeningribs ll provided with openings Ii" through which the air may pass. Theannular wind-box thus formed is supported from the shafts 6 b5 bearingsl3 so that the wind-box is acoommodated in the space between the tworails 6 of the track.

the cooler, as hereinafter described, but it will be noted from Fig. '7that some of the air may pass laterally under the inner edges of thewindbox plates 9 and i0 and would escape to the outside atmosphere ifnot prevented from doing so. We, therefore, provide an air-seal betweenthe wind-box plates 9 and I0 and the corresponding track rails 6. .Theair-seal between the plate I0 and the corresponding track rail 6 maycomprise a sectional ring i8, the sections of which are bolted to amachined surface IS on the plate l0 by means of bolts 20. The outer faceof the sectional ring l8 bears directly against the track rail 6. Figs.l4, l5 and 16 show the details of this sectional ring. There is a slightclearance between the ends of the ring sections, as shown in Figs. 14and 16, through which air is prevented from leaking by means of a spring2| (Fig. 16) positioned in longitudinal slots 22 at the joining ends ofthe ring sections.

A similar sectional air-seal ring 23 bears against the other track rail6. In this case, however, it is clamped to the inner edge of a diaphragm24 by means of a sectional clamping ring 25. The outer edge of thediaphragm 24 is clamped'by means of a sectional clamping ring 26 to aflange 21 carried by the outer plate ll of the wind-box. In addition toa number of cap screws which clamp the ring 25 to the ring 23 there aresome special screws 28 which have inwardly projecting cylindrical heads29 (Fig. 7) surrounding each of which is a helical spring 36. Thesprings 36 react against a machined surface 3| on the side plate 9 ofthe wind-box. It will thus be seen that the springs 30 force the sealingring 23 against its corresponding track rail 6 and at the same timeforce the opposite sealing ring 18 against its corresponding Thewind-box preferably completely encircles I the shell of the cooler, asbest shown in Fig. 1, but so far as some of the features of theinvention are concerned the wind-box may extend only partly around thecooler shell. When the wind-box completely encircles the cooler shell itis preferably formed in at least two sections for convenience inassembling. The sections may be bolted together at the flanges I 4 andi5 (Fig. 1).

The lower portion of the wind-box is connected to an elbow 16 formingpart of an air conduit to which air is supplied by m'eans of a fan IT,or in any other suitable way. The junction of the elbow l6 and thewind-box thus constitutes the air inlet for the wind-box.

The major portion of the air leaving the windbox through its dischargeopening l2 passes through certain openings provided in the shell 'oftrack rail 6. When the track formed by the rails 6 rotates with thecooler shell, the sealing rings l8 and 23 being carried by the wind-boxand thus held stationary, make sliding contact with the inner faces ofthe track rails and thus together withlthe diaphragm 24 prevent any ofthe air that leaves the wind-box from passing to the outside atmosphere.Lubricant, may be supplied to the bearing faces of the sealing rings l8and 23 by pipes l8 and 23', as best shown in Figs. 8 and 1 It will benoted that the wind-box is supported solely by the rotary shell of thecooler, the track and the wheels providing anti-friction means foraccomplishing this. The wind-box remains stationary while the coolershell rotates within it. To hold the wind-box stationary as the coolershell rotates and to adjust its position circumferentially of the shellwhen necessary, the turn buckle shown in Fig.1 is employed. This maycomprise right and left hand eyebolts a2 and a threaded into a longsleeve 34 and locked in position by locknuts 35 and 36. The uppereyebolt 32 is connected to a bracket 31 carried by the wind-box and thelower eyebolt 33 is connected to some fixed point, such as the floor, as

shown at 38. The sleeve 34 is provided with holes 39 by means of whichthe sleeve may be turned with a drift pin. It is obvious that byloosening the lock nuts 35 and 36 and by turning the sleeve 34 thewind-box may be moved a limited distance in either directioncircumferentially about the shell of the cooler after which the locknuts 35 and 36 may be tightened to hold the wind-box in fixed position.To permit this move ment ofth'e wind-box the air conduit between theelbow l6 and the fan II has a section made up of telescopic parts 38 and40, the telescopic joint which may be sealed by a wrapping indicated at4 I. The telescopic part of the conduit is connected to the elbow l6by'a. connecting portion 42 and to the fan IT by a connecting portion43. The joints between these connecting portions and the telescopic partof the conduit are loose ones as indicated at 44 and 45 so that theseveral portions of the conduit will adjust themselves to the newposition of the wind-box. These loose Joints may be provided with asuitable wrapping 06 to prevent air leakage.

Each shaft 8, in addition to being mounted in the bearing iii, is guidedby two forked brackets ll and 48 (Figs. 7 and 9) which are boltedrespectively to the flange 21 at one side of the wind-box and to anextension 49 on the side plate it at the other side of the wind-box.Where the shaft t passes between the arms of the brackets ti and it itis provided with. machined surfaces ht (Fig. 9) on which rectangularwashers ti fit. Each washer it is provided with a slot ti which engageswith the bracket to prevent the washer from turning. The washers arealso provided with holes into which the inner end of adjusting screws itare fitted, these adlusting screws being mounted in the forks of thebracket. By adjusting the screws til the shafts ii, and the wheelscarried by them, may be slightly adjusted to cause the wheels to runtrue on the trash rails t. This adjustment of the shafts t is permittedby the nature of the hearings iii. After each shaft is adjusted by thescrews $3 a slight clearance is left between the washers. iii and themachined surfaces ft on the shaft to permit the shaft to swing slightly(in the plane of the drawing). The bearings it are of such a nature asto permit this movement of the shafts. any irregularities. in the trackand the shell are thus compensated for thereby causing the annularwind-box to ride properly on'the track following the motions of theshell. The shell may thus freely rotate within the annular wind-honwithout disturbing its proper alignment.

The shell 3 of the cooler is provided with a series of openings (whichalso pass through the reinforcing band i) which move directly under thedischarge opening it of the wind-box.

The air passing through these openings into the cooler first enters aircompartments positioned at the interior surface of the; shell and whichwill now be described.

The side walls of the air compartments are formed by a cage which isassembled as shown in Figs. 10-13. The cage comprises longitudinalpartitions t and end circumferential partitions it and 57. as we preferto have two circumferential rows of air compartments instead of one,there is provided an intermediate partition 58 so positionedlongitudinally of the shell that to the right of this partition. asviewed in Figs. 11-13, there is one circumferential row of relativelylong air compartments, and to the left of this partition anothercircumferential row of relatively short air compartments. Thelongitudinal and circumferential partitions may be suitablyinterconnected by means of brackets 59 and splice plates 59a.Circumferential straps 59' and M" are provided which are made up ofsections welded to the splice plates 591: secured to the longitudinalpartitions. The cage is bolted to the shell by means of brackets 60.

Each of the shorter air compartments has one cover plate and each of thelonger air compartwhich projects the eye of an eyebolt 63. A pin,

64 passes transversely through the walls of the boss 62 and through theeye in the eyebolt. The boss 62 rests upon a supporting block orpedestal 65 which is bolted to the shell as shown at 66 (Fig. 4). Theupper portion of the supporting block 65 is provided with longitudinalribs 61. between which the square -boss on the cover plate fits so as toprevent the cover plate from turning. The shank of the eyebolt 63 passesthrough a central opening it in the pedestal 65 and projects through theshell. t where a nut 69 is threaded on its extremity and thereby clampsthe cover plate to the pedestal.

Each cover plate ti is inclined or curved from its leading edge tie toits trailing edge 6th toward the axis of the cooler (Fig. a). Thetrailing edge hit of each plate slightly overlaps the leading edge oftin of the succeeding plate so as to form a slot-like opening it throughwhich air may escape from the air compartment under the cover plate intothe interior of the cooler where it passes through the material therein,as hereinaiter described. The cover plates may, if desired, be providedwith openings or slots ll through which air may also pass from the aircompartments into the interior of the cooler. The cover plates are alsopreferably provided with strengthening ribs if. The adjoining ends ofthe cover plates ti lie over the circumferential straps it and ti".

A sectional discharge ring lit, bolted to the shell t as shown at ill,insures that a certain layer of material will remain on the cover platesiii during the operation of the apparatus.

It will be noted from Figs. 3 and 7 that the plane of the intermediatecircumferential partition ht intersects each of the openings at in thecooler shell. in other words, one part of each of the openings it liesto one side of this partition while the remaining part lies to the otherside of the partition. Thus the air entering the air compartmentsthrough the openings til would normally be divided so that part wouldflow to the short air compartments on one side of the partition and partwould flow to the longer air compartments on the other side of thepartition. However, over each opening hi there is a hood it (best shownin Fig. 7) which interrupts the continuity of the partition ht. Thesehoods are part of the cage as shown in Figs. 11 and i2 and are welded inplace when the cage is assembled. Inside of each hood there is a plate Madjustably attached to the cover it of the hood by means of the bolt it.At either side of the plate l t the hood is provided with an openingill. Thus the air entering the air compartments first passes throughthis hood and is divided by the plate M so that part of it passesthrough one hood opening H to the shorter air compartments while therest passes through the other hood opening H to the longer aircompartments. By adjusting the position of the plate H the proportion ofair supplied to the two circumferential rows of air compartments may bechanged. The hoods substantially prevent any solid material which getsin the air compartments from passing out into the wind-box while theypermit free ingress of air from the wind-box into the air compartments.

Mounted within the annular wind-box at either side of the air inlet is ahollow barrier block it (Figs. 1 and These barriers completely span thepassage through the wind-box and therefore determine by their positionthe circumferential length of that portion of the wind-box to which airis admitted. In other words, they do not merely adjust thecircumferential length of the discharge opening I 2 of the wind-box butthey also adjust the circumferential length or volume of the effectivepart of the wind-box. Each barrier block may be adjustedcircumferentially of the wind-box by means of a cap screw I9 whichprojects through a slot 80 (Fig. 2) in the outer wall ll of thewind-box. A washer Ii prevents the escape of air through this slot. Byloosening the cap screw I9 each barrier block may be adjusted a limitedamount circumferentially of the wind-box and is held in adjustedposition when the cap nut is tightened. It is obvious that the distancebetween the two barrier blocks will determine the number of openings 54in the cooler shell through which air is permitted to pass at any onetime into the interior of the cooler, In other words, direct air supplyis substantially cut off to all of the openings 54 except those whichare passing between the barrier blocks. During rotation of the cooler(in the direction of the arrow shown in Fig. l) the material indicatedat M occupies a position somewhat as indicated in this figure, and thebarrier blocks 18 are so positioned that the air will pass through thoseopenings 54 which lie under the material when the cooler is rotating. Itis desirable to let a small amount of air pass by the barrier blocks andinto the portion of the wind-box beyond them so that it may cool thecover plates ii that happen to be above the level of the material. Forthis purpose the transverse wall of each barrier block is provided withan opening 82 (Figs. 5' and 6) which is controlled by a disc 83 threadedon a stem 84. By turning the disc 83 it may be moved toward or away fromthe opening 82 and it therefore acts as an adjustable valve to regulatethe amount of air-permitted to pass through the opening 82.

Projecting outwardly from the side wall 9 of the wind-box are twopartitions 85, one of which is shown in Fig. 8. One of these partitionsis located near one barrier block 18 and the other one is located nearthe other barrier block, as indicated by the dotted lines in Fig. 1. Thepurpose of these partitions is to prevent the air which leaks around theinner edge of the wall 9, within the space bounded by the barrier blocks18, from passing too freely into the rest of the annular wind-box.

When the annular wind-box has been adjusted to its-propercircumferential position by turning the sleeve 34 of the turn buckle,and has been locked in proper position by the lock nuts 35 and 36, andwhen the barrier blocks 18 have been adjusted to their proper positionsto permit air to flow through the desirednumber of openings in theshell, and when the adjusting plates 14 in the hoods I3 have beenproperly set, the apparatus is ready to operate. Air from the fan l'lpasses into the annular wind-box and then through the openings 54 whichare in the zone between the two barrier blocks 18, and into thecorresponding air compartments. If there is only one circumferential rowof air compartments all of the air passing through one of the openings54 passes into the air compartment with which that opening communicates.On the other hand, if there are two circumferentialrows of aircompartments, as shown in the drawing, the

air passing through each shell opening 54 is di-- passes into the aircompartment at the opposite side of this partition. The adjustment ofthe plate 14 will determine the proportion in which the air is admittedto the two compartments at opposite sides of the partition. In somecases it may be desirable to supply a large quantity of air to thecircumferential row of compartments over which the material first passesupon leaving the kiln so as to produce a sudden air quenching of the hotmaterial, and to supply a smaller quantity of air to the other row ofcompartments over which the material later passes to effect a slowercooling or the material in this part of the cooler. However, there maybe other reasons for changing the distribution of air to thecompartments of the two rows, or as above stated there may be only onecircumferential row of air compartments in which case there would be nodivision of the air at all. Moreover, when two circumferential rows ofair compartments are employed the compartments at opposite sides of thepartition 58 may be of the same length, if so desired.

The air leaves the air compartments through the openings II in the coverplates and through the slot-like openings 10 formed between theoverlapping edges of the plates and passes into and through the bed ofmaterial feeding through the cooler.

There is no contact between the rotating shell and the annular wind-boxexcept at the sealing rings l8 and 23,' and there is no wear which mighteventually change the adjustment of the passages, nor can anyinaccuracies in the shell structure, caused for instance by warping dueto heat, result in any change in the amount of air which passes throughthe bed of material.

While we have referred throughout the specification and claims to theuse of air as the cooling medium, some other gaseous fluid may be usedespecially if the material to be treated is affected by oxygen.

It is to be understood that no limitation is-intended where the claimsrefer to the gaseous fluid as air," since this term is used simply forconvenience to mean any gaseous fluid whether a cooling fluid, a heatingone, or one which affects a chemical treatment of the material.

We claim:

1. The combination of a cylindrical shell rotatable about a generallyhorizontal axis, a relatively stationary annular wind-box encircling theshell, means for admitting air from the wind-box through the shell intothe interior of the shell. and anti-friction means operativelyinterposed between the shell and wind-box, the shell acting through saidanti-friction means to provide the sole support for the wind-box.

2. The combination of a cylindrical shell rotatable about a generallyhorizontal axis. a relatively stationary annular wind-box encircling theshell, means for supporting the wind-box solely by the shell comprisinga track mounted on one of said parts and wheels mounted on the other ofsaid parts and running on the track, and means for admitting air fromthe wind-box through the shell into the interior of the same.

3. The combination of a cylindrical shell ro- I tatable about agenerally horizontal axis, a track carried by and encircling said shell,wheels operating on said track, an annular wind-boxrencircling saidshell and supported by said wheels on said track, means for. holding thewind-box stationary as the shell rotates, and means for admitting airfrom the wind-box through the shell into the interior of the same.

4. The. combination of a cylindrical shell rotatable about a generallyhorizontal axis, a pair of track rails carried by and encircling saidshell, at least one pair of wheels operating on the track, a shaft onwhich said wheels are mounted, an annular wind-box encircling said shelland located between said track rails and supported from said shaft,means for holding the wind-box stationary as the shell rotates, andmeans for admitting air from the wind-box through the shell into theinterior of the same.

5. The combination of a rotatable cylindrical shell, a relativelystationary wind-box at least partly encircling the shell and having acircumferentially elongated discharge opening, the shell having a seriesof openings adapted to communicate with said discharge opening andthrough which air may pass from the wind-box into the interior of theshell, an air inlet for the windbox, means interposed between thewind-box and shell through which the shell acts to provide the solesupport for the wind-box, and means connected to the wind-box and to afixed point and operable for adjusting the wind-box circumferentially ofthe shell.

6. The combination of a rotatable cylindrical shell, a relativelystationary wind-box at least partly encircling the shell and havingspaced side walls and a circumferentially elongated discharge opening inits side facing the shell, the shell having a series of openings lyingbetween the side walls of the wind-box and registering successively withsaid discharge opening as the shell rotates to permit air from thewind-box to pass into the interior of the shell, an air inlet for thewind-box, and a barrier within the windbox at either side of said airinlet completely spanning the passage through the wind-box andadjustable circumferentially of the wind-box whereby the circumferentiallength of the portion of the wind-box to which air is admitted by saidinlet may be adjusted.

7. The combination of a rotatable cylindrical shell, means at theinterior surface of a portion of the shell forming two circumferentialrows of air compartments, a circumferential partition separating thecompartments of the two rows, said shell having a circumferential seriesof openings so positioned that one part of each opening lies to one sideof said partition and the remaining part lies to the other side of thepartition, and a relatively stationary wind-box at least partlyencircling the shell and having a discharge opening facing the shell,said shell openings coming successively into registry with saiddischarge opening as the shell rotates whereby air discharged from thewind-box through the shell openings and into said air compartments isdivided by said partition and part passes into the air compartments ofthe row at one side of the partition while the other part of the airpasses into the air compartments of the row at the opposite side of thepartition.

8. The combination of a cylindrical shell ro tatable about a generallyhorizontal axis, means at the interior surface of a portion of the shellforming at least one circumferential row of air compartments, said shellhaving a series of openings each of which communicates with one of saidair compartments, a relatively stationary.

wind-box at least partly encircling the shell and having a dischargeopening adapted to communicate with said shell openings, and a hoodwithin said compartment at each shell opening for substantiallypreventing passage of solid material from the compartment into thewind-box while permitting air from the wind-box to enter thecompartment, said hood including a part extending inward from the wallof the shell around the shell opening and having an air opening andanother part spaced from the shell wall and overlying the shell opening.

9. The combination of a cylindrical shell rotatable about a generallyhorizontal axis, means at the interior surface of a portion of the shellforming two circumferential rows of air compartments, a circumferentialpartition separating the compartments of the two rows, said shell havinga circumferential series of openings so positioned that one part of eachopening lies to one side of said partition and the remaining part liesto the other side of the partition, a relatively stationary wind-box atleast partly encircling the shell and having a discharge opening facingthe shell and under which said shell openings are adapted to move, ahood for each of said shell openings projecting within the shell andsubstantially preventing passage of solid material from the aircompartment into the wind-box but permitting passage of air from thewind-box into the air compartment, and adjustable means in said hood therelative proportions of air entering the compartments at opposite sidesof said partition.

10. The combination of a rotatable cylindrical shell, a relativelystationary wind-box at least partly encircling the shell and having acircumferentially elongated discharge opening facing the shell, theshell having a series of openings adapted to move successively intoregistry with said discharge opening and through which air may pass fromthe wind-box into the interior of the shell, means for supporting thewind-box so that it is out of contact with the shell wall, and a sealfor preventing escape of air from the windbox to the atmosphereincluding a pair of members mounted on the shell to encircle the latterand lying on either side of the wind-box and means on the wind-boxextending throughout the length of the latter and making seating contactwith the members.

11. The combination of a rotatable cylindrical shell, a relativelystationary wind-box at least partly encircling the shell, said wind-boxbeing channel-shaped in cross-section with the opening in the channelfacing the wall of the shell, the shell having a series of openingsadapted to move directly into registry with said opening in the wind-boxand through which air may pass from the wind-box into the interior ofthe shell, means for supporting the wind-box so that it is out ofcontact with the shell wall, a pair of members secured t0 the shell andprojecting radially outward and between which the wind-box ispositioned, and an air seal positioned between each of said members andthe adjacent lateral wall of the wind-box.

12. The combination of a rotatable cylindrical shell, means at theinterior surface of a portion of the shell forming two circumferentialrows of air compartments, a circumferential partition separating thecompartments of one row from those of the other, said shell having acircumferential series oi openings so positioned that one part of eachopening lies at one side of said partition and the remaining partlies'at the other side oi said partition, a relatively stationarywind-box encircling at least part oi the shell and having a dischargeopening racing the shell, said shell openings coming successively intoregistry with said discharge opening as the shell rotates to permit airfrom the wind-box; to flow through the shell openings and into saidcompartments, and adjustable means at each shell opening 101:

' varying the relative proportions oi the quantities of ntering thecompartments at opposite sides of said partition. 4

to plate to said pedestal.

shell. lbnsitudinal andoimumierential partitions mounted against theinner surface oi. a portion oia shell and forming at least onecircumferential row of air. compartments, a cover plate for eachcompartment. a pedestal secured to the shell in each compartment andlying in line with the central portion only of the cover plate, andmeans tor clamplns the central portion of the cover JOHN NARSTED. POVLT. LINDHARD.

' 13. The combination of a. rotating cylindrical CER'I'IFICIATEOFCORRECTION. Patent No.2,268,296. December 50, 191,1.

JOHN NARSTED, ET AL.

It is hereby certified that error appears in the'printed specificationof the above numbered patent requiringcorrection as follows: Page 5,second column, line 514., claim 9, after "hood" insert --forregulat1ng--; and that the said Letters Petent should be read yvith thiscorrection therein.

,that the .same may conform to the record of the case in the PatentQfflce'.

Signed and sealed e113 5rd day. of March, A. 1 19h2.

Henry van Arsdale, (Se'al) Acting commiesioner of Patents.

